Investigation of basic imaging properties in digital radiography. 12. Effect of matrix configuration on spatial resolution.
Investigation of basic imaging properties in digital radiography. 12. Effect of matrix configuration on spatial resolution.
复制标题
数字放射线摄影中基本成像特性的研究。
作者：
Fujita,H;Giger,ML;Doi,K
研究了三种矩阵结构(常规512×512矩阵、双采样矩阵和高分辨率1024×1024矩阵)对像增强器(II)-TV数字射线成像系统分辨率的影响。从理论上推导了三种矩阵结构的光学传递函数的表达式，并利用测量的预采样模拟元件的调制传递函数和数字系统的参数计算了相应的数字调制传递函数(MTF)。此外，利用II-TV系统获得了每种矩阵类型的星形图案体模和手部体模的数字图像。根据我们的结果，我们得出结论，为了提高II-TV数字成像系统的分辨率，不仅需要增加矩阵的大小，而且需要提高II和/或TV摄像机等模拟元件的分辨率。此外，如果系统不能升级到1024×1024矩阵配置，则可以采用具有512×512矩阵的双采样技术。
We investigated the effects of three matrix configurations (a conventional 512×512 matrix, a double‐sampling matrix, and a high‐resolution 1024×1024 matrix) on the resolution properties of an image intensifier (II)–TV digital radiographic imaging system. Expressions for the optical transfer function were derived theoretically for each of the three matrix configurations, and the corresponding digital modulation transfer functions (MTF's) were calculated using the measured MTF's of the presampling analog components and the parameters of the digital system. In addition, digital images of a star pattern phantom and a hand phantom were obtained with the II–TV system for each matrix type. From our results, we conclude that, in order to increase the resolution of an II–TV digital imaging system, it is necessary not only to increase the matrix size, but also to improve the resolution capabilities of analog components such as the II and/or TV camera. In addition, if the system cannot be upgraded to a 1024×1024 matrix configuration, a double‐sampling technique with an 512×512 matrix may be employed.